Recently, semiconductor memories have attracted attention, which include a nonvolatile memory, such as a resistance change memory (e.g., magnetoresistive random access memory (MRAM), phase change random access memory (PRAM), resistive random access memory (ReRAM), etc.) as a memory device.
A typical resistance change memory is configured to differentiate between data “1” and data “0” by changing its resistance through the supply of a current (or the application of a voltage). In addition, a resistance change memory is equipped with a sense amplifier that senses a slight variation in a read current from each memory cell.